One bacterium, called Klebsiella pneumoniae, has been particularly harmful with 15 to 50 percent of cases due to bloodstream infections resistant to carbapenem antibiotics

The European Center for Disease Prevention and Control (ECDC) has found that multi-drug resistant bacteria, or "superbugs," are spreading throughout Europe with resistance to even the strongest antibiotics.

K. pneumoniae has become resistant to antibiotics in Europe, leading to infection in many countries. In fact, K. pneumoniae is even resistant to the most powerful antibiotics called carbapenems.

According to the ECDC, 15 to 50 percent of K. pneumoniae due to bloodstream infections were resistant to carbapenems.

According to Marc Sprenger, ECDC's director, rates of resistance to "last-line" antibiotics such as carbapenems by K. pneumoniae had doubled to 15 percent in 2010 from 7 percent five years ago.

There are two main issues with fighting the superbug: the lack of commercial incentive to invest in last-line antibiotics, and the misuse of antibiotics.

There are very few new antibiotics in development. According to experts, only large drug firms like AstraZeneca are partaking in antibiotic research, and there's a lack of effort in creating new antibiotics that will only be used as a last line of defense.

Antibiotic misuse is a large problem with fighting bacteria. When antibiotics are overused, bacteria find other avenues of surpassing the antibiotics and invading the body. According to Sprenger, countries with the highest rates of multi-drug resistant infections also tend to be the ones with the highest antibiotic use. These countries include Cyprus, Greece, Bulgaria and Hungary.

But K. pneumonia isn't the only superbug to worry about. A different risk report focuses on a gene called New Delhi metallo-beta-lactamase (NDM-1), which can be found in K. pneumonia or E. coli. It makes bacteria resistant to nearly all drugs, and the ECDC reported 106 cases in 13 European countries by the end of March 2011. In late 2010, there were only 77 cases in the same 13 countries. In August 2010, there were patients in South Asia and Britain discovered with the NDM-1 gene.

Experts say doctors are largely to blame for the overuse of antibiotics leading to abuse and eventually resistance. They say patients demand them without needing them and hospitals readily give them out.